The outfit will be tough to top in the fashion department, and Williams may be difficult to defeat on the scoreboard.

Her 27-4 record this year is the best on the women's tour. Last week Williams climbed for the first time since 2003 to second in the rankings, trailing only younger sister Serena.

Defending champion Svetlana Kuznetsova also advanced, while 2009 quarterfinalist Victoria Azarenka was eliminated. Winners on the men's side included Robin Soderling, hoping to mount another run at Roland Garros after upsetting four-time champion Rafael Nadal in the fourth round last year.

Williams' victory was no surprise coming against Schnyder, who fell to 0-11 versus the seven-time Grand Slam champion. But Williams' movement on Court Suzanne Lenglen boded well for matches to come. She attacked aggressively and scrambled after shots, often extending rallies until Schnyder would blow an easy shot.

Another encouraging sign for Williams fans: She played with neither of her often-troublesome knees wrapped.

Tricky footing has always made clay Williams' worst surface. In 13 previous French Open appearances, she reached the semifinals only once — in 2002, when she lost to her sister in the final. She advanced beyond the third round only once in the past five years.

But as part of a career resurgence at age 29, Williams is 13-2 on clay this year.

Against Schnyder, Williams slammed 27 winners and won 12 of 14 points at the net. She also overcame an inconsistent serve.

In the arduous final game she fell behind 15-40, then hit her only two aces. On her first match point, she double-faulted for the eighth time. She finally converted her fourth match point with a forehand winner and raised a triumphant fist.

The tournament began in warm, sunny conditions that had spectators fanning themselves and forming long lines at ice cream stands.

"Roasting," tweeted top British hope Andy Murray, who had a practice session. "No sunblock today wud be an error."

Kuznetsova was sweating at the start. She lost the first six points and first three games, then swept nine games in a row and beat Sorana Cirstea 6-3, 6-1.

Seeded sixth, Kuznetsova arrived at Roland Garros only 1-3 on clay this year, and she drew a dangerous opening opponent in Cirstea, a quarterfinalist a year ago. The match began shortly after 11 a.m., and even in a nearly empty stadium, Kuznetsova found herself a bit rattled.

"Definitely I was a little bit nervous," she said. "It was rough start for me."

The Russian needed 12 minutes to win a game, but she was in control after that. Three times she rallied to take a game after losing the first three points.

"She was down, so she had to change a little bit," Cirstea said. "She went more for her shots, and they went in."

Cirstea squandered chances to get back into the match in the second set, when she failed to convert all four break points.

A year ago, Kuznetsova beat Serena Williams en route to her second Grand Slam championship. But she has not won any titles this year and her record is 9-9, the worst of any top-10 woman.